macro arg containing a comma | simplist fix w/o using a library

Sorry, I'm sure this has been answered endlessly; but I do not want to use any library ...

In my use case I have redefined the open/close quotes, so it is not easy 
to use say "m4_escape(STRING)" in .../autoconf/m4sugar/m4sugar.m4.

I imagine the solution would be to run the argument through another macro
using my quote definitions, which properly protects the comma -- what is the
simplist version of such a macro?

--
thanks!,
Tom